1. Field of the Invention
The present invention relates to a heat dissipating fan and, more particularly, to a heat dissipating fan with an automatic dust removing function.
2. Description of the Related Art
Conventional heat dissipating fans generally include a housing having an air inlet and an air outlet. An impeller is rotatably mounted in the housing and driven by a driving unit also mounted in the housing to draw in ambient air via the air inlet. The air currents drawn into the housing are concentrated before exiting the air outlet to a heat source in an electronic product. The temperature of the heat source during operation is, thus, lowered. However, dust carried by the air currents is liable to accumulate inside the housing at the air inlet, the air outlet, the blades of the impeller, etc., adversely affecting the air input and/or air output and, thus, adversely affecting the heat dissipating effect.
FIG. 1 shows a heat dissipating fan 9 including a housing 91 having an air inlet 911 and an air outlet 912. An impeller 92 is mounted in the housing 91. A plurality of fins 93 is mounted in the air outlet 912. Air currents can be driven by the impeller 92 into the housing 91 via the air inlet 911. The air currents pass through the fins 93 and the air outlet 912 to a heat source of an electronic product. An example of such a blower fan 9 is disclosed in Taiwan Patent No. 1229254. However, dust is liable to accumulate inside the housing 91 after a period of time of use. Since the spacing between the fins 93 is small, the dust is liable to accumulate between the fins 93, significantly reducing the air output and requiring regular manual cleaning.